/*
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 * 
 *       http://www.apache.org/licenses/LICENSE-2.0
 * 
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *  under the License.
 */
package au.com.domlogic.pvc.core.component;

import org.w3c.dom.DocumentFragment;

/**
 * This implementation of {@link PVCComponent} provides a base class for
 * development following the Decorator Pattern.
 *
 * @author Domenic Figliomeni
 */
public abstract class PVCComponentDecorator
        extends CompositeDocumentFragment implements PVCComponent {

    protected PVCComponentDecorator(PVCComponent component) {
        this.setUnderlyingDocumentFragment(component);
    }

    /**
     * This method implements the interface method by following the Decorator Pattern.
     * After gluePVC() is called on the underlying {@link DocumentFragment}, the abstract
     * method decorate() is called on this concrete instance.
     * @return the {@link DocumentFragment}
     */
    @Override
    public DocumentFragment gluePVC() {
        ((PVCComponent) this.getUnderlyingDocumentFragment()).gluePVC();
        decorate();
        return this;
    }

    /**
     * The implementing subclass will use this method to perform any operations
     * on the component, probably using standard DOM Methods.  The
     * {@link DocumentFragment}, which is at the root of this component can be
     * referenced using 'this' keyword within a subclass.
     */
    protected abstract void decorate();
}
